J. Mater. Sci. Technol. ›› 2021, Vol. 88: 258-269.DOI: 10.1016/j.jmst.2021.01.068

Previous Articles    

Corrosion mechanism of CuAl-NiC abradable seal coating system—The influence of porosity, multiphase, and multilayer structure on the corrosion failure

Yumeng Nia,b, Fan Zhangc, Demian I. Njokua, Yingjie Yua,b, Jinshan Pand, Meijiang Menga, Ying Lia,e,*()   

  1. aCorrosion and Protection Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences,Shenyang, 110016, China
    bSchool of Material Science and Technology, University of Science and Technology of China, Shenyang, 110016, China
    cDepartment of Engineering and Design, School of Engineering and Informatics, University of Sussex, Brighton, BN1 9RH, United Kingdom
    dDivision of Surface and Corrosion Science, KTH Royal Institute of Technology, Drottning Kristinas väg. 51, SE-100 44, Stockholm, Sweden
    eShenyang National Laboratory for Materials Science, Northeastern University, Shenyang, 110819, China
  • Received:2020-10-29 Revised:2021-01-07 Accepted:2021-01-24 Published:2021-03-19 Online:2021-03-19
  • Contact: Ying Li
  • About author:* Corrosion and Protection Division, Shenyang NationalLaboratory for Materials Science, Institute of Metal Research, Chinese Academy ofSciences, Shenyang, 110016, China.E-mail address: liying@imr.ac.cn (Y. Li).

Abstract:

In this study, the corrosion behavior of the CuAl-NiC abradable seal coating system in chloride solution was investigated to systematically research the effect of porosity, multiphase, and multilayer structure on the corrosion failure. Through the composition and structure analysis, the corrosion process of the system was predicted and then verified with mercury intrusion porosimetry, cross-section SEM/EDS analysis, and electrochemical measurements. The results demonstrated that the interphase selective corrosion caused the porosity of the top layer to decrease first and then increase during the corrosion development. The interlayer galvanic corrosion, determined by the pore connectivity, is crucial for corrosion failure.

Key words: Abradable seal coating system, Galvanic corrosion, Multilayer, Porosity